Is there a way I could use a boolean to assign a biome for the user in this rpg?

Question

I have been trying to figure out a way to create a boolean to determine which biome the user chose based on their input using a scanner. But I have not been able to find a way to implement it. I have tried to use boolean return methods but I kept on getting null or the exact opposite biome I was trying to go for.

File: game.java

    public boolean isPlains() {
        if (biome == "Plains") {
            return true; 
        } else {
            return false;
        }
   }

   public boolean isTundra() {
        if (biome == "Tundra") {
            return true; 
        } else {
            return false;
        }
    }

File: phase.java

public class phase extends game{
    public void battle() {
        game gm = new game(); 

   if (isPlains() == true) {
        System.out.println("Hello");
    } else {
        System.out.println("Bye");
    }
}
}

Above is the test run I've tried to run, but whenever I try and run the code it seems to output the opposite I ask it to. I tried flipping it around but it seems to do the same thing. I am trying to use the isPlains/isTundra methods from game.java to determine whether to print hello or bye from phase.java.